Machine-readable codes are known. The most widely known representatives thereof are barcodes (or bar codes, stripe codes, line codes), such as those used on many products. Known formats for such barcodes are EAN, UPC, IAN, JAN and codes from the 2/5 family, as well as codes in accordance with Code 39, Code 93, Codebar, Code 128, etc.
Moreover, “two-dimensional” (2D) barcodes are also known, which correspond, for example, to the code block format of Code 49, PDF417, or other formats in which encoded data can be resolved along two dimensions. Known two-dimensional codes are matrix codes, such as, e.g. Data Matrix codes, MaxiCodes, or the Aztec Code. Especially since 1994, the QR code is also a known representative of the 2D code, because it can encode a large amount of data, and also contains an error correction. It is also advantageous that QR codes can be used without licensing costs.